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Re: Hybird MF14

Posted: Wed Jun 09, 2021 9:54 pm
by Fuzz
Jaysen wrote: Wed Jun 09, 2021 7:46 pm Am I the only one that is both excited and depressed when chenier posts updates?
I am pretty sure it is amazement in my case. Well throw some talent envy in there with it :wink:

Re: Hybird MF14

Posted: Fri Jun 11, 2021 12:52 am
by Netpackrat
Truly first class workmanship. Love the homebuilt bronze fittings.

Re: Hybird MF14

Posted: Sun Jun 13, 2021 4:15 pm
by Chenier
Time for the mundane: I made ventilation plates. These replace the solid inspection hatch covers during the off-season allowing the hull to air out a bit. Screens keep critters out.

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I took the hatch covers ruined by incompatible paints (months ago) and cut half-moons in them with a hot knife. Kept a handle in the middle because they twist on a coarse thread into the hatch seat. Then drilled holes around the rim and sewed on aluminum screen with 18-gauge copper wire.

Let me tell you, sewing with copper wire isn't in danger of becoming a big fad. :roll: On to mast-making ...

Re: Hybird MF14

Posted: Tue Jul 13, 2021 8:37 pm
by Chenier
As I mentioned a bunch of pages back, I obtained an old Sunfish rig, including sail, for a song. The only problem was the mast was bent down near the deck end. Bummer. But, the original Sunfish mast was a hybrid: four feet of aluminum tube topped with six feed of wooden mast. Well, my bent mast has more than four feet of straight tube at the top, so that's what I'm doing.

The original Sunfish spars were derived from the wooden Sailfish, just made a bit longer. Kent Lewis documented the Sailfish spars here if you're curious:

http://smallboatrestoration.blogspot.co ... sions.html

Before starting on the mast, I did a couple of trials at sparmaking on a 3-foot long 2x4 cut in half lengthwise. Conveniently, the resulting 1-1/2 inch square pieces are the same dimensions as the boom and gaff that I'll be making so it seemed like a good test. The tests were successful and good practice, so I set out to make the wood portion of the mast.

I began with a 2-1/4" square blank of laminated Douglas Fir, which you can see below. It's marked out to have a slight taper as well as a sheave (pulley) for the halyard embedded at the top, just like the original.

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In sparmaking, the drill is to knock off all the corners in an organized fashion, such that you turn a square into an octagon. Knock off the corners of the octagon and you get a 16-sided polygon. Wash, rinse, repeat. Here's the first corner planed off, developing the octagon:

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You can see the mortise that I chopped out for the sheave near the top of the mast. That's the first mortise I have created ever. There was not a 3/8-inch mortise chisel to be had anywhere in North America, so I made do. It's adequate, but I'm not in danger of putting any fine furniture makers out of business.

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Little old mast maker.

Re: Hybird MF14

Posted: Tue Jul 13, 2021 8:44 pm
by Chenier
Here's the blank taken down to a 32-sided polygon.

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That's a triacontadigon if you must know. All the lines on the end were to help lay out the starting octagon. The arrow was to give me a reference as I rotated the piece.

Once at 32 sides, the next step is sand it round. I did that by hand on the test pieces and decided it was a lot of work. Then I said to myself: "Self, you have a lathe that makes things spin." My lathe is for metalworking. It's powerful enough but it's way too short. But this is sanding, not precision machining. So I took the tailstock off and set it up with a live center on some wood blocks six feet away.

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Dang, that worked. One morning of sanding got the mast round, the next morning got it smooth to 220 grit.

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Re: Hybird MF14

Posted: Wed Jul 14, 2021 6:32 am
by cape man
Nicely done.

Re: Hybird MF14

Posted: Wed Jul 14, 2021 7:57 am
by Jeff
Agree, very nice!!! Jeff

Re: Hybird MF14

Posted: Wed Jul 14, 2021 11:58 am
by OrangeQuest
Wow! this is just amazing work!

Re: Hybird MF14

Posted: Thu Jul 15, 2021 5:50 am
by Netpackrat
Just because you got a great result doesn't make it not wrong to turn dead tree carcasses on a metal lathe! :lol:

Re: Hybird MF14

Posted: Sat Jul 24, 2021 4:17 pm
by Chenier
Having been suitably chastised and now repentant, :D I rounded the top end of the mast by hand.

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Then I built a 15-foot worktable to do the rest of my spar-building

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And cut a 4-foot straight section out of the old Sunfish mast

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The wide-angle lens on my phone makes it look longer than it really is.